Portable metal straightening device



Oct. 18, 1960 E. D. HOUGEN PORTABLE METAL STRAIGHTENING DEVICE FiledFeb. 21, 1958 fli /91577 0. #OUGf/V 22 BY 27 Hi w a mmm ATTORNEYSPORTABLE METAL STRAIGHTENING DEVICE Everett D. Hougen, Blair EquipmentCompany, 902 Blair St., Flint, Mich.

Filed Feb. 21, 1958, Ser. No. 716,817

19 Claims. (Cl. 81-15) This invention relates to a tool or device foruse in straightening bent sheet metal panels. The tool or device of thepresent invention is especially adapted for use in automotive panelrepair Work.

Heretofore, there have been proposed many different tools or devices forstraightening bent automotive panels, but none of these have proved tobe entirely successful. Ideally, such a device or tool should beportable, easy to assemble and be capable of being easily andconveniently attached to a bent sheet metal panel. From the standpointof the ease of use, such a tool or device, which normally includes ajack either of the mechanical or hydraulic ram type with tubular membersextending from each end thereof, should be capable of being readilyengageable with clamps secured to the bent panel; but, at the same time,the device should be so constructed that after the force on the jack isreleased, the jack can be pivoted to one side without completelydetaching it from both clamps so that the results of the forceapplication can be viewed and analyzed and the jack can then be pivotedback into position if the application of further force is indicated.

Furthermore, to reduce the effort required in using the device, itshould be designed so that the clamps may be first attached to the bentpanel at the desired locations and then the jack with its tubularextensions can be slipped aired States Patent into engagement with oneof the clamps, pivoted into alignment with the other clamp and thenslipped into engagement with the other clamp. In view of the fact thatmost hydraulic rams used for this purpose are of the self-retractingtype, the device should also be designed so as to remain in place on thepanel even when pressure is not being applied to the panel. The deviceshould be capable of applying force to a panel along a line gen erallyparallel to the axis of the jack; but, at the same time, the clampsshould be capable of rotating 360 while still being rigidly attached totheir respective tubular members.

This latter feature is especially desirable in connection with thestraightening of the edge portions of door panels because it enablesmoving bent edge portions back into their original position whileapplying a straightening force to such bent edge portions. The latterfeature is also desirable because it enables moving of only one of theclamp members to a new location while the jack and the tubular membersare still rigidly connected to the other clamp and then re-engagement ofthe tubular member with the moved clamp so as to apply a force to thepanel in a second direction.

To enable the use of a single set of clamps for a variety of differentstraightening operations, the clamps should be designed so that they canbe applied to an edge of a panel and in such position, apply astraightening force to the edge while permitting the operator to hammeror otherwise work the edge being straightened without interference fromthe device.

The present invention provides a device or tool embodying all of theabove mentioned features.

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In the drawings:

Fig. 1 is an elevational view showing two clamps made in accordance withthis invention securing the ends of a jack to opposite edges of a curvedsurfaced work piece which is shown in dotted lines.

Fig. 2 is a plan view showing a clamp applied to adjacent edges of aWork piece which is shown in dotted lines.

Fig. 3 is a sectional view of a clamp in use taken on line 33 of Fig. 4with the jack and the work piece being shown in dotted lines.

Fig. 4 is a sectional view of the clamp in use taken on line 4--4 ofFig. 3.

In the drawings, a conventional hydraulic jack or ram is indicated at 4and tubular members extending from opposite ends thereof are indicatedat 3. As shown, clamps 1 are mounted on the free end portions of thetubular members 3. Referring more particularly to Figs. 3 and 4, eachclamp 1 includes a sleeve 2 which is adapted to receive or telescopeover a tubular member 3. A series of diametrically opposed holes orapertures 5 are provided in each sleeve 2. Holes 5 are arranged in pairsand are spaced axially along the sleeve 2 to permit a bolt 6 to beinserted therethrough. The members 3 are correspondingly provided withapertures 7 therein which are spaced axially along the members 3 so thatthe sleeves 2 can be adjusted along the members 3 and the bolt 6inserted through registering apertures on the sleeve 2 and the member 3to fix the sleeve 2 on the member 3 in a desired position of adjustment.On one side, each sleeve has a centrally located bearing 8 thereon, thebearing 8 being located at a position substantially from the apertures5. The bearing 8 may advantageously be in the form of a nut welded tosleeve 2 and having a threaded opening 9 into which a pintle 11 in theform of a bolt or cap screw can be threaded. The head of bolt 11 isindicated at 12. It will be observed that the axis of opening 9 andpintle 11 is slightly inclined to the radial plane of sleeve 2. Theamount of this inclination is preferably about 7.

The means for gripping the sheet metal comprises a pair of jaw members15, 22. The upper jaw member 15 comprises a fiat plate having anin-turned end portion 17, the free edge of which is serrated as at 18.The fiat face portion of jaw 15 is provided with a generally centrallylocated aperture 16 therein through which the shank 13 of bolt 11 mayextend. Thus, as shown in Fig. 3, the sleeve 2 is supported on the upperjaw 15 so that it can rotate in a plane generally parallel to the planeof jaw 15 through 360.

Upper jaw 15 and lower jaw 22 are provided with registering openings 19,27 through which bolts 26 extend. Lower jaw 22 comprises a flat plateturned inwardly at its opposite ends as at 23 and 25. The up standingend 25 of jaw 22 is provided with an aperture 26, the axis of which isperpendicular to the axis of aperture 13. The upstanding end 23 of lowerjaw 22 is serrated along its free edge as at 24 so that the opposedserrated surfaces 18, 24 are adapted to grip opposite faces of a sheetmetal panel. In the assembled relation of the members, the plane of jawmember 15 is generally parallel to the plane of jaw member 22.

In use, when it is desired to straighten a bent body panel of anautomotive vehicle such as a door illustrated at 30, the two clamps 1are securely engaged with edge portions of the panel at the desiredlocations. In mounting the clamps 1 on the edge portions 31 of panel 36,the upper and lower jaws are separated so that the serrated edgeportions 18, 24 can be arranged against the opposite faces of the edgeportion of the panel. Thereafter, the bolts 20 are tightened to firmlydesired position to an edge 31 of panel 30, the jack-- 4 with itstubular extensions 3 is then engagedwith the clamps. This isaccomplished by slipping one-of'the tubular members 3 through one of thesleeves 2, then pivoting the jack 4 and rotating the other sleeve 2 intoalignment so that the jack can be shifted axially in the oppositedirection'to-engage the other en'd member 3 within the other sleeve 2.Thereafter, bolts 6 are passed throughthe registering'openings in'th'etwo sleeves and the two tubular members 3 so that the clamps are fixedaxially with respect to the tubular members 31 When the-tool is thusmountedon the'panel'to be straightened, hydraulic pressure canbe appliedto the jack 4 to apply a force in tension to the panel 30 between thetwo-clamps. After an initial'force in; tension is applied to the panel,the pressure'on' the jack 4- may be relieved. With the pressurerelieved, the jack remainsassembled and the operator can determinewhether further pressuremust be applied. In some instances, one of-thebolts 6 can be withdrawnfrorn the registering openings in one of thetubular members 3 andth'e corresponding sleeve 2; and if the jack 4 isof the selfretracting type, the loosened tubular member 3 may beretracted to an extent such that it disengages fromwithin the sleeve 2.In any event, without-removing either of the two clamps 1 from the edgeof the panel, one of the tubular members 3 can be retracted from withinits associated sleeve 2 and the whole assembly of the jack may bepivoted about the pintle 11 of one clamp to a position out of the wayenabling the operator to observe the results'of the first forceapplication to determine whether additional force-should be applied tothe panel.

It will be observed that with this arrangement, when one of the tubularextensions Sis disengaged from its associated sleeve 2, the assembly isstill' self-supporting in the sense that the jack assembly is stillrigidly connected to the sleeve 2 of the other clamp. The operator maydecide that the next application of force-should be applied to aslightly different location, in which'case one of the clamps may beloosened and shifted-along the edge of the panel to anew locationandthenre-engaged with the corresponding tubular member 3.

In this connection, it will be noted that the axes fthe sleeves 2 areslightly inclined to the plane of the .jaws. This permits the clamps tobe afiixed to the edges 31 of the panel; and since the planes of theseedges are usually inclined relative to each other by reason of thecurvature or crown in the panel 30, it 'is unnecessary to bend the edgesof the panel in order to engagethe. tubular members 3 in the sleeves 2.It will be appreciated that if the planes of the jaws were parallel tothe axes of the sleeves 2, in most instances, it'would benecessary tobend the panel in order to bring the ends of the tubular members 3 intoalignment with the sleeves 2 of both clamps. This bendingor distortion,in most cases, would probably take the formof a crease at theintersection of the panel and the outer edge of the jaws as indicated at32 in Fig. 3.

By rotating the sleeves 2 through 180 on the jaw members about thepintles 11, a 14 variation is obtained in the angle between the axes ofthe sleeve 2 and the plane of the associated jaw member, therebyproviding adjustment for accommodating various special conditions whichmight be encountered in practice. Since the tubular member 3 has arather loose fitwithin the sleeve 2, a certain amount of play'willnaturally result between 4. these parts and this will, in effect,increase the range of adjustment;

With some types of damage, such as a bent door panel, it is necessary tostraighten the edge itself of the door. Under such circumstances, thetwo clamps 1 can be engaged with the bent edge of the door and thesleeves 2 can be connected with the jaws by inserting the bolts 11through the openings 26 rather than the openings 16. In view of the factthat the sleeves 2 can rotate freely on the jaws, it will be appreciatedthat a force in tension can be applied to the edge of the door and thiswill tend to straighten the edge because the jaws are free to rotatewith respect to the sleeves 2 in accordance with the straighteningaction that takes place. In other words, as the planes of the'twogripped edge portions of the door slowly rotate into alignment, the jawsgripping these edge portions likewise rotate relative to the sleeves 2that are fixed on the tubular members 3 of the jack.

In addition, in an arrangement where the edge of a door is beingstraightened inthemanner described, it will be appreciatedthat bymounting the sleeves 2 by means of the apertures 26, the jack 4 and thetubular members3 will be'ofiset'to one side of the edge of the door.This enables the operator to hammer or otherwise work the bent edge ofthe door between the clamps while the edge is being-tensioned.

Thus, it will be seen thatthe present invention provides a tool forstraightening sheet metal panels, and particularly automotive bodypanels, that incorporates all of the features referredto previously. Itis light weight and portable, andthe design is suchthat it is relativelyinexpensive and within the means of the ordinary collision shop. Asdescribed above, the tool of the present invention is veryeasilya'ssembled and disassembled and-very easily applied to a bent bodypanel for performing a particular straightening operation. The fact thatit is self-supportingto an extent that the entire jack assembly can besupported by one of the sleeves 2 renders its use very convenient! Thus,it can be used very readily by a single person to perform-various typesof straightening operations.

This application is a continuation-in-part of my copending applicationSerial No; 362,784, filed June 19, 1953, now abandoned.

I claim:

1. A clamp for gripping sheet metal comprising an upper jaw member, alower jaw member, said jaw members having fixed, substantially flatsheet metal gripping portions along a pair of'ju'xtaposed edges thereofand being relatively-pivotal along a pair of juxtaposed edges oppositesaid first mentioned edges about an axis generally parallel to' theplane'of said gripping: portions, whereby said jaw members may be openedand closed about said pivotal axis'to separate and bring together saidgripping portions, one of said jaw members having an aperturetherethrough extending generally perpendicular to the plane of saidgripping portionswhen-said gripping portions are closed, a stud memberextending through said aperture, a sleeve adapted for connection with aforce supplying member, a bearing member fixed on said sleeve, saidbearing member having a hore therein inclined slightly to a planeperpendicular to the longitudinal axis of said sleeve, said studmember'having an end portion in said bore and forming a pivotalconnection between said one jaw member and said sleeve.

2. The combination called for in claim 1 wherein one of said jaw membershas an aperture therein the axis of which is generally perpendicular tothe axis of said first mentioned aperture when said jawv members areclosed, said stud member being optionally receivable in either of saidapertures.

3. The combination called for in claim 2' wherein the axis'ofsaid'second'aperture lies generally in the plane of said grippingportions when the jaw members are c ose 4. The combination called for inclaim 1 wherein the axis of said bore in said bearing member is inclinedto a plane normal to the axis of the sleeve at an angle of about 7.

5. The combination called for in claim 1 wherein said stud member isthreaded at one end and provided with a head at its opposite end, saidbore of said bearing member being threadedly engaged with the threadedportion of the stud member, said stud member extending through said onejaw with the head disposed on one side of the jaw and the bearing memberon the other side.

6. In a clamp structure for use with a sheet metal straightening tool ofthe type including a jack having cylindrical members extending from itsopposite ends, the combination of means for connecting the cylindricalmembers to a sheet metal panel for applying a straightening force to thepanel, comprising a pair of sleeves adapted to slidably receive thecylindrical members, means for interconnecting the sleeves with thecylindrical members in a plurality of fixed positions spaced axiallyalong the cylindrical members, a pair of sheet metal clamp members,means connecting each sleeve to one of said clamp members, said lastmentioned connecting means including a pivot between each clamp memberand its respective sleeve which retains the sleeve rigidly on the clampmember in one plane and permits rotation of the sleeve relative to theclamp member in another plane generally perpendicular to the firstmentioned plane.

7. The combination called for in claim 6 wherein the clamp members eachcomprises a pair of jaws and means independent of said last mentionedconnecting means for actuating the jaws toward and away from one anotherto grip and release a sheet metal panel therebetween.

8. The combination called for in claim 7 wherein one jaw of each set hasan opening therein and said pivotal connection comprises a pintleextending through said Opening and secured to said sleeve in a positiongenerally perpendicular to the longitudinal axis of the sleeve, wherebythe sleeve is free to pivot on said jaw in a plane generallyperpendicular to the axis of the pintle, the pintle having asufiiciently close fit with said opening to prevent substantial axialtilting of the pintle in said opening.

9. The combination called for in claim 8 wherein the inner diameters ofthe sleeves generally correspond with the outer diameters of thecylindrical members and have an axial extent such that when one set ofthe jaws is clamped on a sheet metal panel with one of said cylindricalmembers engaged within the sleeve of said clamping jaws, the jack withits cylindrical members are supported in cantilever fashion for rotationin a plane generally perpendicular to the axis of the pintle.

10. In a clamp structure for use with a sheet metal straightening toolof the type including a jack having cylindrical members extending fromits opposite ends, the combination of means for connecting thecylindrical members to a sheet metal panel for applying a straighteningforce to the panel, comprising a pair of sleeves adapted to slidablyreceive the cylindrical members, means for interconnecting the sleeveswith the cylindrical members in a plurality of fixed positions spacedaxially along the cylindrical members, a pair of sheet metal clampmembers, means connecting each sleeve to one of said clamp memberscomprising a pintle extending generally perpendicular to the axis of thesleeve, said pintle having a connection at one end with the wall of thesleeve and having a connection at its opposite end with the clampingmember, one of said connections permitting rotation of the sleeverelative to the clamp member in a plane generally perpendicular to theaxis of the pintle and both of said connections restricting relativemovement of the sleeve and clamp member to said last mentioned rotativemovement.

11. The combination called for in claim 10 wherein said clamp memberseach comprises a pair of separable jaws, said pintle being connectedwith one of said jaws and means independent of said pintle for closingand opening the jaws, whereby to grip and release a portion of a sheetmetal panel therebetween.

12. The combination called for in claim 10- wherein said one pivotalconnection permits rotation of the sleeve in said plane through 360*".

13. The combination called for in claim 10 wherein the pintle isinclined slightly to the radial plane of the sleeve.

14. In a clamp structure for use with a sheet metal straightening toolof the type including a jack having cylindrical members extending fromits opposite ends, the combination of means for connecting thecylindrical members to a sheet metal panel for applying a straighteningforce to the panel, comprising a pair of sleeves adapted to slidablyreceive the cylindrical members, means for interconnecting the sleeveswith the cylindrical members in a plurality of fixed positions spacedaxially along the cylindrical members, a pair of sheet metal clampmembers each comprising a pair of separable jaws having juxtaposedclamping faces, means for closing and opening the jaws to grip a portionof a sheet metal panel between said clamping faces, one of said jawshaving an opening therein which is generally perpendicular to the planeof said clamping faces, a pintle extending axially through said openingand being axially rotatable therein, the end of said pintle exteriorlyof said jaw being rigidly connected with said sleeve in a positiongenerally perpendicular to the longitudinal axis of the sleeve, wherebythe sleeve is rotatable on said jaw in a plane generally parallel tosaid clamping faces.

15. The combination called for in claim 14 wherein one jaw in each sethas an opening therethrough, the axis of which is generallyperpendicular to the axis of said first mentioned opening, said pintlebeing optionally insertable through either of said openings so that thesleeve can be mounted on the jaws for rotation in a plane which iseither generally parallel to or generally perpendicular to the plane ofthe clamping faces.

16. The combination called for in claim 15 wherein the axis of saidsecond mentioned opening l-ies generally in the plane of said clampingfaces when the jaws are closed.

17. The combination called for in claim 16 wherein said clamping facesare disposed adjacent one end of the jaws and the jaws are 'fulcrumedrelative to each other adjacent the ends thereof opposite said clampingfaces, said second mentioned opening being located at said lastmentioned end of said one jaw.

18. The combination called for in claim 17 wherein said first mentionedopening is located generally centrally between the opposite ends of saidone jaw and the second mentioned opening is located generally centrallybetween the opposite side edges of said one jaw.

19. The combination called for in claim 18 wherein said pintle comprisesa headed screw and the sleeve has a threaded member secured to the wallthereof in which the threaded end of the screw is adapted to bethreaded.

References Cited in the file of this patent UNITED STATES PATENTS2,606,467 Deszarlais et al. Aug. 12, 1952 2,608,730 Killus Sept. 2, 19522,734,549 Thorley Feb. 14, 1956 2,736,359 Bowman Feb. 28, 1956

